De Beers, the world’s biggest diamond producer, had its smallest sale of the stones so far this year as demand was hurt by India’s crackdown on black money.

The company sold US$418 million of diamonds in its 10th cycle, compared with $476 million at its previous offering, according to a statement on Tuesday. For the same period last year, sales were $248 million.

“While the trade in lower-value rough diamonds is experiencing a temporary slowdown as a result of the demonetization programme in India, demand across the rest of the product mix continued to be healthy,” Chief Executive Officer Bruce Cleaver said. “Overall sales remained in line with seasonal expectations.”

The industry has been hit by India’s war against so-called black money after the government invalidated existing 500-rupee (US$7.41) and 1,000-rupee bank notes. De Beers has responded by moving to ease restrictions on buyers in India as the government’s actions suppressed demand.

The former diamond monopoly allowed select buyers to pass on boxes of the cheaper stones even if they’ve used up their allowance of deferrals, according to people familiar with the deals who asked not to be identified because the information isn’t public.

De Beers, a unit of Anglo American Plc, has also taken the unusual step of permitting buyers to refuse lower-quality stones from pre-mixed assortments of diamonds, they said.

The diamond industry is seasonal, with the holiday season from Thanksgiving in November through Asia’s Lunar New Year in January or early February ranking as the busiest period for jewellery sales. De Beers’s customers buy more rough stones earlier in the year to prepare for this period.